Automatic telephone system



APPLICATION FILED JUNE IB, 19H.

4 SHEETSSHEET I Patented Jan. 10, 1922.

H. H. TUE. AUTOMATIC TELEPHONE SYSTEM. APPLICATION FILED JUNE 18. I917.

Patented Jan. 10,1922.

4 SHEETs-SHEET 2 5 fin/527F511" 1922"!" Hide.

1/! 11.2f Iroa H. H., IDE. AUTOMATIC TELEPHONE SYSTEM- nrmcmou FILED mus 18. m1.

Patented Jan. 10, 1922.

4 SHEETS-SHEET 3.

Zia/277,511 Harry/VH5 H. H. IDE.

AUTOMATIC TELEPHONE SYSTEM.

APPLICATION FILED JUNE 18, 19H.

2 m 0 1 m m m a P UNITED STATES PATENT OFFICE.

HARRY H. IDE, OF LA GRANGE, ILLINOIS, ASSIGNOR TO KELLOGG SWITGHBOARD AND SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

AUTOMATIC TELEBHONE SYSTEM.

Application filed June 18, 1917.

'10 all whom it may concern:

Be it known that I, HARRY H. IDE, a citizen of the United States of America, residing at La Grange, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Automatic Telephone Systems, of which the following is a specification.

My invention relates to automatic telephone systems in which automatic switches known as the two-dimensions type are employed, these switches comprising bank con tacts divided into groups and cooperating wipers adapted to receive a rirnary adjustment to select a group of contacts, and thereafter a secondary adjustment to select a contavt in the selected group. My invention has to do more particularly with the mechanical construction of the switches of the above type and with the circuit arrangements adapted for use with these switches.

Prior to this. switches having the above characteristics and provided with a single operating shaft, usually employ an extra release magnet to be operated to allow the wipers to be restored, or where no release magnet is employed. the wipers are aided by gravity in their restoration.

An object of my invention is to provide a single operating shaft for a switch which has no extra release magnet and which has the wipers restored. by sprin tension, and not by gravity, thus provi( ing a switch which is most positive and sensitive in its operation as well as simple in construction.

A further object of my invention'is the means employed for adjustably attaching or securing the contact banks to the mounting plate which carries the switch mechanism.

Further objects of my invention reside in the means provided to operate the off-normal contacts, the novel manner in which the holding and driving pawls are controlled, and the unique method of restoring the switch shaft to normal.

However, the main object of my invention is to produce an improved switch which embodies desirable features and advantages all in a simple, etlicient and economical manner, which is most efficient and economical in its operation, and which has its parts so constructed and combined as to make them readily accessible for repair and adjustment.

Other features of my invention will be Specification of Letters Patent.

Patented Jan. 10, 1922.

Serial No. 175,364.

more particularly pointed out in the followingspecification and in the appended claims.

or a more complete understanding of my invention, reference may behad to the accompanying drawings in which like reference characters denote like parts in the different views, and in which:

Fig. 1 is a front elevation of the switch structure embodying my invention;

Fig. 2 is a left side elevation of the structure illustrated in Fig. 1;

Fig. 3 is a right side elevation of Fig. 1;

Fig. 4 is a sectional view on the line 44 of Fig. 1, showing the primary off-normal springs;

Fig. 5 is a sectional view on the line 5-5 of Fig. 1, showing the secondary off-normal springs;

Fig. 6 is an enlarged view of a portion of the switch showing the driving ratchet and retaining pawls;

F i 7 is an enlarged'sectional View of the switc shaft;

Fig. 8 is a view of a portion of a switch bank and its associated wiper;

Fig. 9 is a partial section showing the method of mounting the driving magnets to their heel irons;

Fig. 10 is a view showing the adjustable stop for the driving pawl of the secondary ma net of the switch;

Big. 11 is a side view of the primary operating mechanism showing certain parts broken away, and

Fig. 12, which comprises parts 1 and 2 is a diagrammatic illustration of the circuit arrangement adapted to be used in connection with the switch structure of my invention.

Referring now to the switch structure of my invention, as shown in Figs. 1 to 11, inclusive, it comprises a frame F on which are mounted all of the movable parts for operating the Wipers of the switch, and to which I also attach the banks of contacts. To support the banks of contacts A and B upon the frame F, I provide a pair of brackets 2 which are securely fastened to the frame F by means of the screws 3, a pair of screws 3 being provided for each bracket 2. The brackets 2 have bifurcated portions 2 into which the posts 4 fit, said posts 4 being securely held to the brackets 2 by means of clamping nuts 5. The banks of contacts A and B are adjustably secured to the post 4, as will be presently described. The UPpr3hflnk.CORt&tS;AlmI-)F15e the private; hankecontaets as they areicommoniy known in the art, which include one hundred contacts 6, arranged inlte'n horizontal rows of ten each. The lower bank of contaets :B adjus ably-sewm t th post .4 and comprises the two sets of line contacts, namely, the vertical and rotary contacts 17 and 8, as they are commonly known in the art, there bing one hun dred pairs of contacts'arranged inten horizontal rows, ten pairs of contacts to each row. Thebank ofprivate contacts is securely clamped betweenthe clamping plates'9 and 10. The individual contacts that form the bank of contacts are suitably insulated from each other,-as-clearly illustrated in'Fig. 8. The contacts of each row are radially disposed and arepla-ced between pieces of insulation cloth 11 and 12, anda-strip of'insulating material 13,. sue-has micarta or some other suitable ;material, is placed between-each of said rows of contacts. The ten rows of contacts are placed between the clamp ng plates 9 and 10 and clamped together to formthe bank of contacts A. The bolts and nuts 16 form the clamping means for securing the rowsofcontaets togethcras a whole.

The vertical and rotary contacts are secnrely clamped between the clamping'plates 17 and 18, and are suitably insulated from each other in a manner Similar to that just described in connection with the prinate bank A. Afurther description is therefore deemed unnecessary. To secure'the private bank A to the supporting post 4. I. provide the lower clamping plate 10 with cars 19 preferably formed integrally with sard plate 10 and bent over parallel to the plane of the plate proper. The plates 9 and 10 and portions 10 of plate 10 are provided with openings 19 to receive the posts 4. The bank A as a whole is slipped on the posts 4.- and when inthe desired proper-position the screws 20 are tiahtene'dtomamtain the bank inthis position. The screws 20 have screw threaded engagement with the ear portions 10 of the plate 10. The bank B which comprises the line contacts is similarly secured to the post 4. The lower clamping plate 18 is provided with cars 18 which serve the purpose as above described, and further description is not deemed necessary.

Adapted to co-operate with the contacts 6. 7 and 8 are.the wipers 21, 22 and 23, the said wipers being mounted upon the shaft 24 and suitahlv insulated therefrom. The wiper 21. which is operatively associated with the private bank contacts 6, is c0mmonly known in the art as the private wiper, and is mounted upon the shaft 24 by means of a U-shaped carrier 25. The parallel arms of the U-shaped carrier 25 have suitable openings 26 whichpermit the carrier 25 120 he slipped onto the shaft2ei. The wiper 21 has a portion 21 U-shaped in construction, and suitably fastened to the portion 25 of the carrier 25 by means of the screws 27, thesaid wiper 21 being suitably insulated from the shaft 24 and the screws 27. Thewiper 21and carrier 25 as a whole are slipped upon the shaft 2 1 and when in the proper relation with the contacts of private bank A are clamped to the shaft '24 by means of the set screws 28 and lock nut 29. The wipers 22 and 23, which are commonly knewnin the art asthe line wipers, are also mounted insulatingly uporra car rier 30, by means of the screws The carrier 30 and the wipers 22 and 23, as a whole, are mounted upon the shaft 24 in operative relation with the contacts of the line bank {B by means of the set screw 31 and lock nut 32, the wipers being-suitably insulated from each other and also insulated from the carrier 30. The shaft 24 carries the wipers 21, 22 and 23in a primary downward and a secondary rotary direction.

The frame F has a portion 35 bent at right angles to the vertical portion of the said frame F to form mounting means for the sleeve 38. which sleeve is suitably fastened to the frame portion 35 by means of the screws 39. The sleeve 38 acts as-snspending means for the shaft 24 and also forms one of the bearings for the said shaft 24-. A sleeve 40 is also provided. which sleeve is supported by the frame F. and serves. as a bearing for the other end of shaft 24. The sleeve 40 also acts as a bearing for the ratchet wheel 41 which operates to drive the shaft 24 in a secondary direction. A. spring casing 42 is also mounted upon the sleeve bearing 40 and contains a spiral spring 43. the said spring 43 having one end fastened to the casing 42 and the other end fastened to the sleeve 40. The tension of the said spring 43 is such that it hasa tendency to hold the shaft 24 in its normal position, that is. it normally retains the wipers of the shaft 24 to the left of the rows of bank contacts. The sleeve 40 has one end threaded, and its other end is provided with a flanged portion. The said flanged end rests in a recess in the ratchet 41. A collar 1-1 is slipped over the sleeve 40, and its upper peripheral surfare fm'ni-s a bearing for the drums that contains the rotary restoringl spring 42: and the lower portion of the said coilar 44 is provided with a reduced portion 44 thatiits into a suitable orifice 45 in the frame F. I provide a nut 4-7 and awloclc nut 48 which have screw threaded engagement with the threaded portion of the sleeve 40, and when a proper ad justment of the ratchet 4:1 and parts is the sleeve 38.

secured the said nut 47 and 48 are tightened to secure the sleeve 40 in adjusted position- A coil spring 50 is provided and has its one and secured to a reduced screw threaded portion 51. of a plug 52. which plug in turn has screw threaded engagement with A look nut 53 is provided for locking the plug 52 in its adjusted position in the sleeve 38 The said spring 5U passes through a suitable cylindrical opening 24, extending the full length of the shaft 24, and has its louver end attached to the hook shaped portion of a plate as. The plate 56 fits into a slot 57 cut in the lower extremity of the shaft 24. The spring 50 maintains the shaft 2i in its normal vertical position and due to the fact that this spring is quite long extending the full length of the shaft. the yielding force that it exerts upon the shaft 24 is not materially changed when the said shaft is moved down Ward the full distance that it is permitted to travel.

The shaft 24 when in its normal position rests against a suitable piece of material 59, such as ruhhen which is inserted in an annular orifice in the plug 52, the said plug serving as a stop for the shaft and the insert 59, to deadeh the noise when the shaft is restored to normal by the spring 50. The plug 52, which has screw threaded engage ment with the sleeve 38 serves as an adjusting means to determine the normal vertical position that the shaft 2st is to occupy, and when this position is secured the lock nut 53 is tightened to keep the said plug 52 in its proper position. The shaft 52 is provided with circularly cut ratchet teeth 61] which are acted upon by a driving pawl to move the shaft 24 in a downward primary direction to move the wipers 21. 22 and 23 to a pro determined group of contacts in the private bank A, and in the line hank B.

The primary magnet PM, which is adapted to move the shaft 24' and wipers 21, and 23 in a primary downward direction includes a pole piece 62 an armature 69, and a driving pawl 8h. The magnet (Si is suitably secured to the pole piece 62 by means of a screw 63 which passes through a stud illsaid screw 63 having screw threaded engagemeat with the core of the ole trimmgnet 6!. The stud (it through whih the screw 63 passes serves as adjusting means for the electromagnet (it in an up or down direction, and has screw thr aded engagement with the heel iron 62. the oth r and ot the stud (ti luv ing provided with an integrally formed. her;- agonal head (35. To adjust the electromagnet 6t. the screw ('53 is loosened and the stud 6% turned to the right or left as the case may he. to properly adjust the magnet. and when this adjustment obtained a lock nut as is tightened to hold the stud in its adjusted position. Pole piece 62 has projecting cars (5? bent at right angles to the main part of said pole piece, and the said ears have suitable openings to receive a pivot pin 68, which pin pivotally supports the armature (it) of primary magnet PM. The armature (39 also provided with cars which have suitable openings to receive the pivot pin 68. A U-shaped member 71 is also provided (see Fig. 5), the arms of which have suitable openings for receiving the pivot pin 68. To pivotally support the armature 69 upon the pole piece the pivot pin (38 is inserted through the openings in the cars (57 and T0 of the pole piece and the armature, and through the openings in the arms of the U- shaped mcmher 71. One ear of the member Tl tits hctwcen one of the supporting cars 67 of the pole piece and the adjacent car '70 of the armature. A set screw 72 is provided and has screw threaded engagement with the yoke end of the U-shaped piece 71. The said screw 72 is used to securely hold the pivot pin (38 in place relative to the heel iron 62 and the armature 69. A coil spring 7 3 for holding the armature 69 in its normal position has its one and fastened to a screw ('8 which passes through an orifice in the frame F, and its other and fastened to an adjustable screw 75, which screw passes through a suitable opening in the armature 69 and has screw threaded engagement with a saddle member 76. An extended portion 77 of the pole piece is bent forward at right angles and is provided with an adjustable stop screw 79 for securing the proper air gap hetwoen the armature 69 and core of the slew tromagnct til. The primary magnet PM as a whole is fastened to the frame F by means of screws 79 which pass through suitable openings in the frame F, the said screws having screw threaded engagement with the pole piece 62. The free end of the armature (it) pivotally supports a driving pawl 80, the said pawl 80 being adapted to engage the ratchet teeth (30 on the shaft 24; to move the sa id shalt downward against the tension of spring 50.

In the operation of the primary magnet Phi the miniature 69 is attracted, moving away from the stop 79, and during this movement a leaf spring 81 suitably fastened to the armature 6!) by means of a screw 81 acts upon the pawl 80, rotating the said pawl St) about its pivot and into engagement with the teeth 60 of the primary ratchet upon the shaft 24-, and the armature 69 continuing in its unn'cmont moves the shaft :24- in a downward direction until the pawl 80 engages a stop the said stop being preferably formed integrally with the pole piece (52. This movement oi the shaft 24 moves the wipers 21. 522 and 23 one step in a downward direction. A retaining pawl 83 is provided which is pivotally secured to a U-shaped member 8 lby means of a pin 84 which has i llll lac

s-rew threaded engagement with one of the arms of the U-shaped member 84. The mem her 84 is secured to the stop by means of screws. The retaining pawl is held in the teeth 60 of the ratchet by a leaf sprin g 85 which is suitably clamped between the U- shaped member 84 and the stop 82. A guid ing arm 86 is provided which is preferably formed integrally with the retaining pawl 83. Upon the retraction of the armature 69. due to the spring 73, the pawl engages the arm 86 to disengage said pawl from a tooth 60 of the ratchet on the shaft 24, and upon the attraction of armature 09 the guide arm 86 acts to properly guide the pawl 80 into the next tooth of the ratchet 00. Upon each actuation of the primary magnet PM. the shaft 24. and the Wipers 22 and 23 are moved downward one step from a position opposite one row of contacts 6. 7. and 8 to the next. 7

I provide a set of primary off-normal contacts PON which are moved to their alter nate position upon the first step of the shaft 24 in a primary downward direction. A mounting plate 90 is suitably fastened to the frame F, upon which the primary ofi" normal contacts PON are insulatingly mounted by means of insulated screws 91. A rod 92 is pivotally supported by ears 93 which are integrally formed in the plate 90. An arm 95 is supported upon the rod 92 by means of a set screw 96, the said arm 95 having an insulation button 97 which operates the primary off-normal contacts PON when the rod 92 is o erated. The rod 92 extends through the rame F and has its lower portion 92 bent in such a manner that it engages and is operated by the U- shaped wiper carrier 25. Upon the first step of the shaft 24 in a downward primary direction, the U-shaped carrier 25 disengages the portion 92 of the rod 92 so that the off-normal springs PON which are normally under tension, due to the arm 95 engaging the said springs, force the arm 95 to the right. This movement of arm 95 causes the rod 92 to rotate about its pivot. and also allows the said springs PON to move to their alternate position. The primary off-normal contacts PON are again restored to normal upon the restoration of the shaft 24 by the spring 50. The carrier 25 again engaging the portion 92 of the rod 92, moves the arm 95 to the left and forces the primary off-normal contacts PON into their normal position.

The secondary magnet SM, which steps the shaft 24 and wipers 21, 22 and 23 in their secondary rotary direction, is provided with a suitable pole piece 101. The magnet SM is adjustably mounted to the pole piece 101 in a manner similar to that previously described in connection with the primary magnet PM so that a further description is unnecessary. The electromagnet 100 and pole piece 101. as a whole, are fastoned to the frame F by means of the screws 102'. Pivoted to the forward end of the pole piece 101 is an armature 102 carrying a pivoted pawl 103 which is normally held against an adjustable screw stop 104 by means of a leaf spring 99. The leaf spring 99 is held in place by a screw 99. The screw 104has screw threaded engagement with a post 105 suitably fastened to the frame F by means of the nut 106 (Fig. 1.) The armature 102 is held in its normal position by means of the coil spring 107, the said coil spring having one end fastened to a pin 108, the said pin being staked to the pole piece 101, and the other end is adjustably secured to a screw 110. The screw 110 passes through a suitable opening in a plate 111. which plate is suitably fastened to the armature 102 by means of screws 112, and is provided with an adjusting nut 113. The tension of the said spring 107 is regulated by means of said nut 113. A set of interrupter springs I are associated with the secondary magnet SM. the said springs being insulatingly mounted upon the pole piece 101.by means of the insulated screws 114. The interrupter springs are held in their normal position by means of an arm 115 which is preferably formed integrally with the plate 111, the said arm 115 being .provided with a rubber buffer which operates the springs of the set. An adjustable screw 116 is provided which has screw-threaded engagement with the pole piece 101 and acts as a stop for the arm 115 when the said arm is in normal position. A plate 120 is pivotally secured to the ratchet 41 by means of a screw 121. A screw 122, having screw threaded engagement with the ratchet 41. passes through a slot 123 in the plate 120 and permits a limited movement of the plate 120 about the pivot screw 121. The portion 120 of the plate 120 is bent at right angles to form a nose which fits into a vertical s ot 125 cut in the shaft 24 for purposes to be presently described. A stop 126 is mounted upon the ratchet 41 by means of the screws 127 and limits the return of the shaft 24. An adjustable screw 128. which has screw threaded engagement with the post 105, is provided for the stop 126. A lock nut 129 is provided which locks the said screw 128 in its adjusted position. The pivot screw 121 and one of the screws 12?, which are diametrically oppositeeach other. have reduced ends 127 and 121 (Fig. 7) in the form of pins which enter suitable openings in the spring; casing 42 to keep the said spring casing 42 and ratchet 41 in proper relation. A retaining pawl 130 op eratively associated with the ratchet 41 is pivotally supported upon the frame F by means of a pivot screw 131. The said pawl 130 is held in its normal position by means of a U-shaped member 132 secured to the rod 92 by means of a set screw 133. An arm 134 formed integrally with the pawl 130 engages a downwardly extended arm 135 of the U-shaped member 132, so that upon the first step of the shaft in a primary downward direction the rod 92 rotates as previously described, rotatingthe U-shaped member to the right, causing the arm 135 to disengage arm 134. The pawl 130, being under tension of a coil spring 136, moves about its pivot 131. thereby permitting the pawl 130 to engage the teeth of the ratchet 41. When the secondary magnet SM is energized, its armature 102 is attracted, and during the movement of the said armature 1.02 leaf spring 99 acts upon the pawl 103, rotating the said pawl about its pivot into proper engagement with a tooth of the ratchet 41, and the armature continuing its movement causes the pawl 106 to rotate the said ratchet 41 until the said pawl engages the adjustable stop 146 mounted upon the frame F.

The rotation of the ratchet 41 by the pawl 103 causes the shaft 24 to be rotated through the medium of the angular portion 126 of the plate 120 which engages slot 125 of shaft 24, thereby rotating the shaft and wipers one step in a secondary direction. The re taining pawl 130 engaging a tooth in the ratchet wheel 41 prevents the back rotation of the shaft 24. Upon the retraction of armature 102 by the spring 107, the driving pawl 103 discngages the tooth of the ratchet 41 and assumes a position to engage the next tooth of the said ratchet 41. The stop 141) is fastened to the under side of the frame 1! by means of a screw 141 (Fig. 10) which extends through a slot 142 in the said stop 140. said screw 141 having screw threaded enga ement with the frame F. A post 142; is sultably fastened to the under side of the frame, and supports an adjusting screw 143 which has screw threaded engagement with the angular portion 140 of stop 140. The stop 140 may be moved forward or backwurd by loosening the screw 141 and turn ing the adjusting screw 143 then when the proper adjustment of the stop 140 is obtained the Screw 141 is ti htened. The adjusting screw 143 is provit ed with a lock nut 144 to lock the said stop in its adjusted position.

I provide a set of secondary off-normal contacts SON which are moved to their alter-- nate position upon the first step of the shaft in a secondary direction. The contacts SON are insulatingly mounted upon the frame 90 by means of the insulated screws 150. A U-shaped member 151 provided with a pair of arms 152 and 153 is loosely pivoted upon the rod 92. The arm 153 normally engages a stud 154 which is suitably fastened tothe plate 120. The arm 152 has an insulation button 155 secured to it. The said button normally engages a sprin of the secondary oil-normal switch SON. Vhen in the position shown in Fig. 5, the secondary oflinormal contacts SON are at normal and upon the-first step of the shaft 24 in a secondary direction, the stud 154 moves away from the arm 153, thereby permitting the U-shaped member 151 to turn about its pivot point and the sprin 's SON to assume their alternate position. Upon the restoration of the shaft 24 to normal, the contacts SON are caused to return to normal by the stud 154 engaging the arm 153, thus rotating the member 151 and causing the arm 152 to be moved to restore the -s'aid secondary offnormal contacts SON.

A curved leaf spring 320 is provided for normally maintaining the feather 120 in its normal position in slot 125 of shaft 24. One end of the said spring is firmly secured to said feather 120 and the other end of said spring en ages the stop 126. When the shaft has con rotated to its releasing post tion, the stud 154 engages the vertical holding dog 83 and turns the plate 120 about its pivot point, loosening the guide 120 in the slot 125 of the shaft 24. A further result due to the stud 154 engaging the holding dog 83 is the removal of the holding dog from engagement with the teeth 66 of the shaft 24. The removal of the feather 12%) from the slot 125 and the removal of the vertical holding pawl permits the shaftto restore vertically to its vertical normal position. The stud 154 is made eccentrically so that it may be adjusted to limit the amount that the vertical holding pawl is moved out of engagement with the teeth 66 of the shaft 24.

Secured to the vertical part of the frame i by means of suitable bolts and nuts is a relay mounting plate 160, upon which are mounted the relays that control the operations of the switch. A strip of insulation 161 is provided having suitable slots to recelVe the U-shaped terminals 162. A retaining block 163, also of insulating material, is placed on top of the block 161 and the said strip 161, block 163 and terminals 162 are then mounted, as a whole, upon the member 160 by means of screws 164. A cover plate 165 is provided to which the spring jacks 166 are insulatingly mounted in a suitable manner, the said terminals 162 being adapted to be inserted between the said spring jacks 166 to complete the necessary electrical circuits. The cover plate 165 is mounted to a suitable frame 167 by means of bolts andnuts168, the said cover being provided with a pair of pins 169, one on each side wall, suitably fastened thereto. Member 160 is provided with L-shaped or bayonet slots 170 in each wall into which the pins 169 fit, the switch, as a whole, being suspended by the said pins to the cover plate 165. To remove'the switch,*asa1whole, from its" supporting pins 169, the said switch is moved upward until the" horiaentai'portion of the L-shaped slot 170 is in line with the pins 169, and when in this position, the switch may be removed from its" support by pulling it forward.

The switch is made up of certain units which are detachably secured to the frame F; the primary magnet PM' including all of the parts carried thereby to form a unit may be removed from the frame by takin out the s rews 79 and another substitute The secondary magnet SM and'the parts car ried thereby a so form a unit and may be removed by taking out the screws 102 and replaced by another one. To remove the shaft and wipers, as a whole, the spring 50 is removed from the hook 55 thus allowing the shaft to be withdrawn and permitting another shaft to be inserted. It will thus be seen from the foregoing description that should either of the magnets, or any of the parts carried thereby, be in need of repair they may be readily replaced by other units without disturbing other parts of the switch.

in the operation of the switch, the primary magnet PM is alternately energized and de-energize-d, causing the pawl 80 to engage successive teeth of the ratchet 60 to step the shaft 24 and Wipers 21, 22 and 23 in a downward primary direction from one group of contacts to the next, the retaining pawl 83 engaging successive teeth of the ratchet 60 to prevent the shaft from restoring. Portion 92 of the rod 92 disengages the carrier 25, allowing the primary offnormal contacts PON to assume their alternate position, as already described. Upon the first step of the shaft 24 in a primary downward direction. the pawl 130 is allowed to move into engagement with a tooth of the ra chet 41. this movement being brought about by the rotation of the rod 92 when the. carrier 25 disengages the rod 92. When the secondary magnet SM is alternately energized and de-energized the pawl 103 en- .crages succe sive teeth of the ratchet 41, cansing the shaft 24 and wipers 21. 22 and 23 to he stepped in a secondary rotary direction from one set of contacts to the next. Upon the first step of the wipers in a secondary rotarv direction. the stud 154 disengages the arm 153, al owing the secondary oil' normal contacts SON to assume their alternate position. The retaining pawl 130 also engages successive teeth of the ratchet wheel 41, preventing the release of the switch shaft. In the release ofthe switch aftr the wipers'21. 22 and 23 have been moved to engage a set of bank contacts 6. 7 and 8, secondary magnet SM is again alternately energised and de-enerzed to rotate the wipers until the said wipers 21, ahead 23 have beenedvanced one step beyond the last set of the contacts 6 7 and 8. As the shaft and wipers are advanced to this position, the'stud 154 engages the retaining pawl 83, as before described, moving it out of engagement with a tooth of the ratchet 60 upon shaft 24, allowing spring 50 which was tensioned by the movement of of the shaft 24 in a downward direction to restore the shaft 24 and wipers 21, 22 and 23 upward, until the top of the shaft engages the buffer 59. The stud 154 engaging retaining pawl 83 moves feather 126 out of the slot 125 of shaft 24 a suflicient amount to permit the shaft to restore vertically. The removal of the feather from the slot lessens the frictionof the feather in the slot. thereby permitting the use of a li hter spring 50 for returning the shaft. When in this position, the carrier 25 engages portion 92 of the rod 92, rotating the said rod, causing the aim 135 of the member 132 to engage the arm 1340f the retaining pawl 130 causing the pawl 130 to disengage a tooth of the ratchet wheel 41, the spring 43 now restoring the wipers and shaft to their normal position. The shaft is stopped in its normal position by the Stop 126 engaging the screw stop 129. The stud 1.54 engages the arm 153 upon the restoration of the shaft to normal, bringing about the restoration to normal of the secondary off-normal contacts SON, the primary offnormal contacts PON having been restored to normal when the carrier 25 engaged the portion 92 upon the upward movement of the shaft 24.

I represent diagrammatically in Fig. 12, the complete circuit arrangement necessary for connecting a calling subscriber to a called subscriber. The said circuit shows a calling substation R terminating in an individual line switch S. The line switch S is adapted to connect with an idle first selector T. The first selector T in turn is adaptelll to connect wirh an idle connector U, and the connector U is adapted to connect with the terminals of the called substation V. The called substation V also terminates in an individual line switch S. The circuits shown for the selector T and the connector U are adapted to work with the switch structure shown in Figs. 1 to 11. inclusive. It is t be understood. however. that the switch structure shown may be used in connection with various other circuit arrangements and, likewise, the circuits shown are adapted for use with other switch structures. In order to more fullv understand the circuits as pointed out. Fig. 12, Part 2. is to he placed at the right of Fig. 12. Part 1. to form a continuation thereof and a complete circuit.

The substation R includes the usual talkin equipment of a common battery telephone with the addition of the calling switch CD, adapted to break the continuity of the subscribers line circuit. The circuit for the subscribers substation R will be carried through a series of continuations, finally establishing connection with the subscribers telephone V which is also shown as having an individual line switch at the central ex change.

The line switch S is provided with a 1'otary shaft that carries a private test contact 208 and a pair of line contacts or wipers 209 and 210. A line relay LR is provided which is energized over the subscribers line conductors in series. A cut-ofl relay CO is also provided for disconnecting the subscribers line circuit from the relay LR and for connecting the switch wipers to the subscribers line circuit. A motor magnet 201 is provided for stepping the switch wipers step by step over the bank contacts 211, 212 and 213. A11 il-normal switch ON is provided which is actuated with each first step of the wipers The switch wipers are spring restored and are adapted to be released to normal when the cut-off relay CO is tie-energized.

As herein-before mentioned, the switch structure shown in Figs. 1 to 11, inclusive. is adapted for use as a selector T or as a connector U, it only being necessary to change the combination of the off-normal springs and to add additional relays to control the circuits required. Of course, the secondary operating magnet of the connector U is not provided with interrupter contacts as the connector l does not perform a secondary selecting operation but rather a seconadry electing operation in picking out the contacts of the desired called line. The relay mounting bridge 100 of the connector U is made of eullicient size to carry the extra relays needed for controlling the circuits of the connector.

Assuming now, for instance, that a call is to be traced from the calling substation it to the called substation V, upon the re" moral of the receiver by the subscriber at the substation R a circuit for the line relay LR of the individual line switch B is estal lished, this circuit being traced from battery through the winding of relay LR, normal contact 200 of relay 201, normal contact 20?? of the off-normal switch ON, normal contact 20 of relay (l0, and through the closed contacts of the substation switch hook to ground at normal contact 205 of relay CO. The line relay LR, upon cner ization, establishes an energizing circuit or the relay 201. The said circuit for relay 201 extends from battery through the winding of the relay 20 normal contact 206 of said relay 201, and alternate contact 207 of relay LR to ground. The opening of normal contact 200 of relay 201 o )ens the energizing circuit of the line relay 1R, deenergizing the said relays and causing the wipers 208, 209 and 210 of the line switch. S to engage the first set of contaets 211, 212 and 213. U on the first step of the switch shaft, the '0 -normal contacts ON assume their alternate position, and contacts 211 and 215 are also moved to their alternate position. The opening of alternate contact 207 of line relay LR brings about the de-energization of the relay 201, and should the private wiper 208 of the line switch S engage a busy contact 211, upon the first ste a substitute circuit for the line relay LB 18 established, traced from battery through the winding of relay LR, normal contact 200 of relay 201, alternate contact 203 of othnormal contacts ON, and alternate contact 215 to ground at the busy contact engaged by private wiper 208. The closure of the alternate contact 207 of the line relay LR again establishes a circuit for relay 201, as previously described, causing the switch wipers to take another step and engage the second set of contacts 21]., 212 and 213. If the next private con tact 211 is busy, relay 201 and line relay LR are again energized and (lo-energized to step the wipers 208, 209 and 210 step by step until an idle private contact 211 is encountered. l-Vhen the contacts leading to an idle first selector T have been found, the line relay LR de-energizes, bringing about the deenergization of the magnet 201. The closing of normal contact 217 of relay LR establishes an energizing circuit for the cutoff relay CO traced from battery through the winding of the said relay CO, conductor 218 and normal contact 217 of relay LR to ground at alternate contact 214. The energization of the relay CO brings about the restoration of the contacts 214 and 215 to their normal position, openin the initial encrgizing circuit of the relay 0. The relay ()1) being slow to release, has a substitute circuit established for it, as will be presently described, before it has had time to de-energize and permit its contacts to return to normal. The wipers 209 and 210 having engaged contacts 212 and 213 of the idle first selector T bring about the energization of the impulse relay IR of the said first selector T over a circuit traced from battery through the right hand winding of the relay Ill, conductor 219, normal contact 220 or the ielay T bank contact 212, wiper 209, alternate contact 205 of relay CO, through the substation and back through alternate contact 204 of relay CO, wiper 210, bsink contact 213, normal contact 22]. of relay T conductor 222, and through the left-hand winding of relay IR to ground. The closing oi alternate contact 223 of relay 1R establishes an energizing circuit for the reay 221 traced from battery through the upper winding of the relay 224, over conductor 225, and through alternate contact 223 of relay IE to ground at normal contact 226 of primary oil-normal contacts FUN. An energizing circuit for the relay 227 isalso establ shed when relay IR is enercontact 211, conductor 231, and alternate contact 232 of relay 224 to ground at alternate contact 228 of relay 227, thus maintain ing the relay CO of the switch S continuously energized until the conversation is terminated. The idle first selector T havin been selected by the line switch S, the su scriber at the calling substation R now actuates his calling device CD to call the first digit of the called number. Assuming that the number of the subscriber of the called substation V is 345, the subscriber at substation R actuates the calling device CI) to send three impulses of current over the line, which impulses bring about three successivc energizations and de-energizations of the impulse relay IR. Upon the first deenergization of the impulse relay IR, the circuit for the primary magnet PM is established, traced from battery through the winding of the magnet Pltl, normal contacts 235 of the secondary oif-normal contacts SON, conductor 236, normal contact 223 and conductor 225 to ground at alternate contact 237 of relay 224. The primary magnet PM is energized and de-energized three times due to the opening and closing of contact 223 of relay IR, which magnet operates to step the wipers 238, 239 and 240 of the first selector T in a downward primary direction to the third group of contacts corresponding with the desired second selector or connector. After the last impulse, the relay 227 de-energizes, due to a circuit being closed through the lower Winding of the relay 227, traced from battery through the winding of the said relay, normal. contact 241 of relay SM, alternate contact 243 of relay IR, and alternate contacts 244 and 226 of primary off-normal contacts PON to ground. The said primary oil-normal contacts PON move to their a ternate positions upon the first step of the wipers of the first selector T. The energizing circuit for relay 227 just mentioned is closed upon the first step of the wipers all normal, but the relay 227 does not de-energize during the sending of impulses due to the construction and adjustment of the said relay 227. The differential relay 227 only receives short impulses of current during the operation of relay IR which do not aflect the relay suiticiently to cause it to tie-energize. as the above-mentioned circuit through the lower windin of relay 227 is permanently closed, the said relay permits its armature to retract. The opening of contact 228 disconnects ground from (onductor 231 at this point but a substitute ground from alternate contact 226 of the primary off-normal contact PON is substituted before said relay 227 ale-energizes. This ground. also places a busy potential upon private contact 211, preventing any other individual line switch from engaging multiples of said contact. The differential relay 224 is not ale-energized during the rapid operation of relay IR and the closure of a circuit through its lower winding, owing to the construction and adjustment of the same. Upon the de-energization of the relay 227, an energizing circuit for the relay 242 is established traced from battery through the winding of the said relay 242, normal contact 247 of relay T normal contact 248 of secondary magnet SM, normal contact 249 of the secondary oil"- normal contact SON, normal contact 228 of relay 227, and alternate contact 232 of relay 224 to ground at alternate contact 226 of primary off-normal contacts PON.

The energization of the relay 242 establishes an energizing circuit for the secondary magnet SM traced from battery through the winding of the said magnet to ground at alternate contact 250 of relay 242. Secondary magnet SM steps the wipers 238 239 and 240 one step in a rotary secondary direction to engage the first set of contacts 251, 252 and 253. The energization of the secondary magnet SM brings about the restoration of the relay 242 due to the opening of normal contact 248 of said magnet SM. The opening of contact 241 of magnet SM again permits the energization of relay 227 by opening the, circuit of its lower winding. The restoration of the relay 242 opens its alternate contact 250, bringing aboutthe restoration of the secondary magnet SM. Upon the first step of the wipers 238, 239 and 240, the secondary off-normal contacts SON assume their alternate position, and the openirjiig of the normal contact 249 of secondary 0 -normal contacts SON removes the initial ground from the relay 242 and should the private wiper 238 of the first selector T engage a contact leading to a busy connector U, an energizing circuit for the relay 242 is again established, traced from battery through the winding of the relay 242, normal contact 247 of relay T normal contact 248 of magnet SM, alternate contact 255 of relay 224, alternate contact 256 of relay 227 and wiper 238 to the grounded busy contact 251. The closing of the alternate contact 250 of relay 242 brings about the energization of secondary magnet SM. The relay 242 and As soon magnet SM are thus alternately energized and ie-energized to step the wipers 238, 239 and Jill in a se ondary horizontal direction to seek the contacts of an idle connector switch. when a contact 251 leading to an idle connector is encountered by the wiper 238, the energizing circuit of the test relay is not again closed, thereby preventing further energi catirms of the secondary magnet SM. It will thu be seen that by this see-saw action of relay 242 and magnet SM a positive driving operation of the secondary magnet is secured and that it is impossible to stop the selector T on a busy contact or to drive the said selector past an idle contact because unless relay 242 is energized magnet SM cannot be energized and relay 242 can only be energized When magnet SM is at normal and private Wiper 268 is resting on a busy contact. The relay 227 does not ole-energize during the secondary movement of the wipers, due to its adjustment and the rapidity of the interruptions of normal contact 24-1 of secondary magnet SM. The closure of normal contact 2&1 of secondary magnet SM after i s last dc energization closes a circuit for the lower winding of the relay 227, as previously described, and due to its differential action it decncrgizes. Upon the restoration of the relay 227, an energizing circuit for the relay T is established traced from battery through the Winding of the said relay T alternate contact 24 9 of the secondary offnormal contacts SON, normal contact 228 of relay 227, alternate contact 232 of rela 224 to ground at alternate contact 226 oi primary oft-normal contacts PON. The opening of normal contacts 220 and 221 of relay '1 opens the energizing circuit of the impulse relay IR, and the closing of normal contact 1523 of said relay IR closes a circuit through the lower winding of the relay 224 traced from battery through the said lower Windingnornial contact 223 of said relay IE, to ;=;round at alternate contact 237 of mid relay 22%. The relay 224, due to its diil'erential winding, neutralizes and'restores to normal. The relay 224 restoring, opens the circuit of relay 227 permitting the said relay 227 to restore. The closing of alternate contacts 220 and 221 of relay T extends the connection of the calling subscriber It to the idle connector U engaged by wipers 2BR. 239 and 240 of selector T. The closing of alternate contacts 220 and 221 of relay T brings about the energization of the impulse relay 1R of connector U from ground through one winding of the relay 5ll bank ('on ac Wiper 240, alternate contact 2 1 of relay T bank contact 213, Wiper 210. alternate contact 204 of relay CO, through the substation R, the alternate contact 205 of relay CO, Wiper 209, bank contact 212, alternate contact 220 of relay T Wiper 239, bani: contact 252, and through the left hand winding of the interrupter relay 1R to battery and ground. The restoration of the relay 224 of the first selector T opens the initial energizing circuit of rela T of the first selector T, but the relay T being slow to release has a substitute circuit established for it,traced from battery through the Winding of said relay, its alternate contact 260, wiper 238, bank contact 251, conductor 261, and conductor 262 to ground at alternate contact 263 of the impulse relay 1R The said relay T remains energized until the termination of the conversation.

The energization of the relay IR brings about the energization of the relays 265 and 266, the circuit of relay 265 extending from battery through the right hand winding of said relay, normal contact 267 of the primary off-normal contacts PON conductor 261 and conductor 262 to round at alternate contact 263 of relay fil The circuit for relay 266 extends from battery through the lower winding of the relay 266, conductor 269, conductor 270, and alternate contact 271 of relay IE to ground at alternate contact 263 of impulse relay IR Upon the energization of relay 265, a locking circuit is closed for the said relay extending from battery through its alternate contact 272 to ground. The subscriber now operates his calling device CD to send four impulses of current over the line. These four impulses bring about four energizations and deenergizations of the relay 1R causing the primary magnet PM to energize and de-energize four'times to step the Wipers 273, 2H and 275 in a downward primary direction to the fourth group of contacts containing the contacts of the called line. The circuit of the primary magnet PM may be traced from battery .through the Winding of the said magnet, normal contact 276 ofswitching relay 'SVV, conductor 277, alternate contact 278 of relay 266, normal contact 271 of relay 1R conductor 262. conductor 261, and non mal contact 267 of the primary off-normal contacts PON? to ground at alternate contact 272 of relay 265. After the primary oil-normal contact 267 has moved on the first step of the switch shaft, the ground fed from contact 287 of relay 288 is substituted for the ground fed through contact 272 of relay 265. After the last impulse of the series has been sent, the steady flow of current through both windings of relay 266 causes the said relay 266, due to its (lllTClt1l tial action, to neutralize and restore its contacts to normal. Relay 266 does not restore during the sending of impulses due to its adjustment, construction and the rapidity of the interruptions of contact 271. The closing of normal contact 281 of relay 266 brings about the energization of the switching relay SlV traced from battery through the Winding otsaid relay to makc-bciore-brcal:

contact 282 of said relay, normal contact 283 of secondary off-normal springs SON, conductor 284, normal contact 281 of relay 266, and conductor 285 to ground at alternate contact 286 of primary off-normal contacts PON the said primary off-normal contacts PON having been moved to their alternate position on the first step of the wipers 273, 274 and 275 of the connector switch. The closing of alternate contact 276 of the switching rela i Sl/V now renders the secondary magnet S l operative so that when the calling subscriber at the substation R actuates his call device again to send the last set of impulses, which we have assumed are live in number, the said magnet SM will be energized and de-energized by the impulse relay 1R five times over a circuit traced from battery through the winding of the said magnet SM, alternate contact 276 of relay SW, conductor 277, alternate contact 278 of relay 266, normal contact 271 of relay 1R conductor 262, conductor 261, and alternate contact 267 of the rimary olfnormal contacts PON and con uctor 289 to ground at normal contact 287 of relay 2,88. The secondary magnet SM now steps the wipers 273, 274 and 275 in a secondary rotary direction to engage contacts 290, 291 and 292 of the called line. Upon the first impulse of the last set, the relay 266 again energizes to permit the secondary magnet SM to be operated, and after the last impulse the relay 266 is again tie-energized, as previously described. The restoration of the rela Y 266 closes a circuit for the test relay T i traced from battery through the windingot the said relay, conductor 293, the alternate contact 294 of relay SYV, (the said relay SWV having been energized and locked up when the differential relay 266 permitted its armature 281 to be retracted) alternate contact 283 of the secondary off-normal contacts SON (said contacts havingbeen moved to their alternate position upon the first step of the wipers in their secondary direction) conductor 284, normal contact 281 of relay 266, conductor 285 to ground at alternate contact 286 of the primary ofi-normal contacts PON The closing of alternate contact 295 of relay TR connects the said relay orer conductor 296 to the test wiper 273, and should be called line be busy the private contact 290 of the called line would be grounded, thus closing a locking circuit for the said relay TR through the private wiper.

' Called Zine idle.

Assuming that the called line is idle, private contact 290 of the called line will have a battery potential upon it, and the relay TR will not remain energized but will decncrgize. The opening of normal contact 300 of relay TR 0 ens the circuit of the switching relay S The relay SW deenergizing opens the circuit for relay TR at its contact 29 1, leaving the relay TR dependent upon the potential found upon the private contact 290 of the called line for its holding potential, and, as assumed, this contact is free from ground potential, therefore the relay TR ole-energizes and returns to normal. The relay T R de-energizing causes the energization of the relay over a cir cuit which may be traced from battery through the cut-off relay CO, to bank contact 290, through wiper 273, conductor 296, normal contact 295 of relay TR, conductor 302, normal contact 303 of relay SV, conductor 304:, through the lower winding oi the relay 288, and conductor 305 to ground at alternate contact 280 of relay 265. The closing of alternate contact 306 of relay 288 short circuits the lower winding of the said relay, and the closing of alternate contact 307 of relay 288 closes a circuit through the upper winding of the said relay through the alternate contact 307 and conductor 305 to ground at alternate contact 280 of relay 265.

The closing of alternate contact 308 of relay 288 connects the interrupter I to the relay 310. The circuit for relay 310 may be traced from battery through the winding of the said relay 310, conductor 311, alternate contact 308 of relay 288, conductor 312, normal contact 313 of relay RC and through the interrupter I to ground. The relay 310 is thus intermittently energized and dc-energized, and upon each de-cnergization of the relay 310 the ringing generator EU: is connected to the called line over a circuit extending from the ungroundcd pole of the generator RG, through normal contact 311 of ringing control relay RC, conductor 315, alternate contact 316 of relay 288, condiutor 317, normal contact 318 of relay 310, wiper 275, bank contact 292, through the condenser and call bell of the called substation back through bank contact 291, wiper 274, normal contact 319 of relay 310, and conductor 320 to ground at alternate contact 287 of relay 288.

The call bell of the called subscriber at the substation V is thus intermittently rung, due to the energization and decnergization of the relay 310 by the interrupter I. When the called subscriber answers and the relay 310 is in its energized position, a circuit for the relay SR is closed, which may be traced from batter through the lower winding of the relay S through alternate contact 31 of relay 310, wiper 275, contact through the now closed contacts of the substation switch hook at the called substation V. back through contact 291, wipen274. alternate contact 3l9 of relay 310 and through the upper winding of the relay SE to ground. The relay SR, upon energizing, closes on energiz ing circuit for the ringing control relay RC. which may be traced from battery through the winding ot the said relay and make-he fore-break contact 322 to ground at alternate contact 323 of relay tilt. The closing of alternate contact 324 of relay RC closes a locking circuit tor the said relay which may be traced il rom battery through the winding of the said relay. its alternate contact 324 and roiuluctor 285 to ground at alternate contact 286 of the primary ott nornial con tacts PUNK The opening, of normal contacts 3 :1 and 314 disconnects the interrupter l and the ringing generator llli to prevent further application of ringing current. A substitute circuit for the relay $510 is now established which may be traced from but tery through the Winding ot the relay 310, conductor 3ll, alternate contact 308 of relay 288. conductor 312, alternate contact 313 o; relay RC. and conductor 285 to ground an alternate contact 286 to primary oft-normal contacts PON. The subscribers are now in conversational circuit, and the talking circuit may be traced over the heavily inarhctl conductors. said conductors having the condenser-s K and K interposed.

The subscribers having finished conyersm tion, and assuming that the subscriber .it the calling Suhstation ll is first to replace his receiver upon the switch hoolcthe opening of the switch hook contacts brings about the tie energization of the impulse relay 1B of the connector l The restoration of the relay 1R brings about the opening of the holding circuit of the relay T of the iirst selector T. The closing of normal contact 347 ot the restored relay T of the first selector T closes an energizing ciriuit for relay 242 which may be traced from battery through the u. ding of said relay 242. normal contact 24'? of relay T normal contact 248 of magnet SM. normal contact 255 of relay i224, and alternate contacts 524% and 226 of primary ott nornial contacts PON to ground. The closing of alternate contact 250 of relay brings about the energization of secondary IfltcfIHGt SM. The relay 24F] and secondary magnet Slvl are alternately energized and (lo-energized (as before described) the secondary magnet SM thus stepping the wipers 533%) and 240 beyond the last contacts of the row of bani; contacts, from which point the wipers are restored to normal by spring tension,

The secondary off-normal contacts SON and primary oft-normal contacts PON are rrstored to normal. and the opening of normal contact of the primary oft-normal contacts POE opens the energizing circuit The subscriber V restoring his receiver of the relay tilt at the switch hook contacts, causing the said relay to (lo-energize. The closing of normal contact 330 of relay SR closes a circuit through the left hand Winding oi the relay 265i which may be traced from battery through the left hand Winding ot' the said relay 25 i alternate Contact 331 of relay 28.1. conductor 332, normal contact 330 of relay t lt and ooiulurtor 333 to ground at normal contact. 26f; oi relay lR. Due to the dill'ercntial construc ion of relay 265. the said relay neutraliz-irs and restores to normal. The closing of normal contact 33 3: of relay 2H3 closes an energizing circuit for the seroiulary nmgnrt t-llvl which may be traced from bait ry through the winding of said secondary magznct H11 conductor normal contact 334 of relay 26o. alternate contact $36 of the primary off-normal contacts ljtill through the interrupter I to ground. The srconilaiy magnet 8M thus steps the wipers 27 274 and 275 beyond the st sot, o t' contar s in the group. The wipers thou rcstigire to normal from this position by spring! tension. The restoration oi the relay 26:3 brings about the opening of the ircut of the relay at alternate contact 280. and the relay 28S restoring opens the circuit oi relay 310 at contact 308 of relay 28S and the primary off-normal contacts PORT having restored upon the restoration oi" the switch. the opening of the alternate contact 286 of PU brings about the dccnergi. ition ot the elay EC. The relay 265 also brings about the dc-cnergization of the cut-ofi relay (.0 of the line circuit S" which is associated with the called subscriber V.

All the apparatus used in establishinx a connection between a calling subscribe; at the substation A and the called subscriber the substation V is now at normal and available for use in establishing other con nections.

..'tssn1ning new that the subscriber at the called suhstation V was first to replace his TGtiQlVUI' upon the switch hook. the opening oi the switch hook contacts at the substation V brings about the tle-energization oi" the relay F ll. Nothing else happens at this time as the relay T11 is still maintained energized over the line of the calling sulstation The callingsubscriber at the substation ll rep acinghis receiver interpts the cir uit of the impulse relay H1 at the switch hoo contacts. The relay lR (lecnergrizing' closes a circuit tor the lefthaml Win-(l ner of relay 265i. causing the said relay to (lo-energize. as herein-before described. The restoration of the individual switch i first selector T and connector ll is the some as previously described from this point on. Should the called subscriber V fail to repla his rccciier upon the switch ill) upon its switch hook interrupts the cireuithooh after the conversation is terminated. 11:0

the replacing of the receiver at the substa own make-before-break contacts to ground lion It brings about the de-energization of the impulse relay IE of connector U, the same as before, and the openin of alternate contact 263% of impulse relay R opens the circuit of the relay T of first selector T as before described. and causes the release of S-9lt.(t()l T and individual line switch S.

The subscriber at the called substation 'l'ailing to replace his receiver, permits the continued energization of the relay SR, thus holding the contact 330 of said relay in its alternate position, preventing the dilferential wound relay 265 from restoring to normal and closing the energizingcircuit for the seir-ondary magnet 3M The relay 266 energizes when the line relay 1R drops back but is immediately restored to normal due to the closure of an energizing circuit through the lower winding of the said relay 266 which may be traced from battery through the said lower winding, conductor 2T0, alternate contact 330, conductor 333, to glOllIlil at alternate contact 263 of the now restored impulse relay 1R Relay 266 being differentially wound, restores to normal. and the closing of normal contact 340 of the said relay 266 places a ground upon the private contact of the connector U over a circuit which may be traced from ground at alternate contact 286 to the primary olfnormal contact PON conductor 285, normal contact 281 of relay 266, conductor 284, alternate contact 283, normal contact 340, alternate contact 341 of the secondary oil'- uormal contacts SON to the private contact 231. The placing of this busy potential upon the private contact prevents any first -?l ('iOI' switch T from engaging the contents of this busy connector.

Called Zine busy.

A ssuming now that the called line is busy, the operation of the circuit is the same up to and including the time that the relay TR momentarily energizes. The line being busy, the private contact 290 has a busy potential placed upon it, thus closing a locking ciruit for the test relay TR fro-m battery through the winding of the said relay, its alternate contact 295, conductor 296, and the wiper 273 to ground at contact 290. The closing of alternate contact 3&2 of the test relay TR connects the busy signal BB to the line to transmit a busy signal to said calling subscriber at substation R, thus notifying him of the busy condition of the said called substation V. Relay RC is also energized when connection is made to a busy line to prevent an application of ringing current from being applied to the called line if the called line should become idle before the connector I is disconnected from the bank contacts of a called subscribers line. The relay RU upon energizing locks up through its at the primary off-normal springs PUN. The calling subscriber now replaces his receiver, bringing about the de-energizationof the impulse relay 1R The relay IR restoring opens the circuit of the relay T of the first selector T which closes a circuit for the secondary relay SM, as previously described, thus bringing about the release of the first selector T and the individual switch 3. The relay IR de-energizing, brings about the restoration of the relay 265, due to the fact that the relay SR has not been energized. The closing of the circuit through the left hand winding of the relay 265 brings about the neutralization of said relay 265. The closing of normal contact 334 of the said relay 265 closes a circuit through the secondary magnet SM an interrupter I, which magnet steps the wipers 273, 274 and 27 5 beyond the last set of contacts. The wipers then restore to normal by spring tension. The primary off-normal contacts POW and secondary off-normal contacts SON are also restored, and the apparatus used in this busy connection is now at normal and available for use in establishing other connections.

lVhile I have shown a system of 1,000 capacity, it is to be understood that by inserting second selectors the system may be increased to a 10,000 system, etc.

It is to be understood that I do not wish to be limited to the exact matter shown, as various other arrangements may readily suggest themselves to one skilled in the art. Therefore, I desire to cover all such changes and modifications as come within the spirit and scope of the appended claims.

What I claim as new and desire to secure by United States Letters Patent is:

1. An automatic switch including groups of contacts arranged in parallel rows, a shaft for said switch provided with wipers for engaging said contacts, step-by-step mechanism for driving the shaft and wipers to a row of contacts, mechanism for thereafter driving said shaft and wipers to a set of said contacts, spring restoring means for restoring said shaft and wipers in one direction, and other spring means for restoring said shaft and wipers in the other direction to normal.

2. An automatic switch including a bank of passive contacts arranged in groups, a

switch shaft provided with wipers adapted,

to be moved vertically to a group of confacts and then rotated into engagement with contacts in a selected group of contacts, electromagnetic means for moving said shaft and wipers vertically, electromagnetic means for thereafter rotating said shaft and wipers beyond said bank of contacts, and suitable spring restoring means for moving said shaft and wipers in two directions over a dilTerent path to restore them to normal position.

3. An automatic switch including a bank of passive contacts, a switch shaft and a wiper carried thereby associated with said bank of contacts. suitable means for primarily driving said shaft and wiper against spring pressure to a group of said passive contactsmeans for secondarily driving said shaft and wiper against spring pressure to move said wiper into engagement with one of said passive contacts, means for thereafter driving said shaft and wiper beyond said bank of contacts whereby said shaft and wiper are restored to normal position by said spring pressure.

1. A switching device including bank contarts arranged in levels, a switch shaft provided with wipers adapted to be moved to a level of contacts and then to a contact in the level, a magnet for driving the said shaft and wipers against opposing spring tension to a level of contacts, a second magnet for then driving said shaft and wipers against opposing spring tension to a contact in the level. and means whereby said second magnet restores the shaft and wipers to normal.

An automatic switch including a bank of passive contacts, a suitable shaft provided with a wiper for co-operating with said passive contacts, means for moving said shaft and wiper in two different diretions to engage one of said passive conta ts. a retarding device effective in each direction of movement. said retardin device becoming active when said shaft an wiper are moved bevond said bank of contacts to restore said shaft and wiper to normal.

(3. An automatic switch including a bank of passive contacts, a switch shaft and a wiper carried thereby associated with said bank of ((ifltilrtS. suitable means for primarily driving said shaft and wiper against spring pressure to a group of said passive ntacts. means for secondarily driving said shaft and wiper against spring pressure to move said wiper into engagement with one of said passive contacts, means for thereafter driving said shaft and wiper beyond said bank of contacts whereby said shaft and wiper are restored.

T. An automatic switch including a switch shaft. step-by-step means for moving said switch shaft in a vertical direction and then in a rotary direction, spring means opposing the movement of said shaft in one direction, other spring means opposing the movement of said shaft in the other directiomboth of said spring means being operable to restore the said switch shaft to normal.

8. An automatic switch including a bank of passive contacts comprising a plurality of parallel rows of contacts, a shaft provided with a wiper for co-operating with said passive contacts, means for moving said Shaft in two different directions to move. said wiper into engagement with one of said passive contacts, and means for moving said wiper beyond said bank of contacts whereby said shaft and wiper are restored by spring means to normal.

9. In an automatic switch, passive coutacts arranged in rows, a movable switch shaft provided with wipers adapted to engage said contacts, an electromagnet and apparatns controlled thereby for moving said shaft in a vertical direction to select a row of contacts, a second electromagnet and stepby-step apparatus controlled thereby for rotating said shaft and wipers to select contacts in the row, the said second electromagnet also being adapted to rotate said wipers to a position beyond the last contact in the row, and a pair of springs for restoring the shaft and wipers to normal position.

10. An automatic switch including a bank of passive contacts, a stcp-b v-step shaft for said switch provided with an active Conta t, means for moving said shaft and active contact against the action of two retarding springs into engagement with one of said passive contacts, and means for continuing the movement of said shaft and wiper beyond said bank, said springs being thereupon effective to restore said shaft and active contact to normal position.

11. An automatic switch including an endwise movable and rotatable switch shaft, an active contait carried by said switch shaft, a bank of passive contacts, means for moving said switch shaft in a vertical direction against the tension of a retarding spring, means for rotating said switch shaft against the tension of a retarding spring, said springs forming means for thereafter returning said switch shaft to normal.

12. An automatic switch including an endwise movable and rotatable switch shaft, a retarding spring opposing the endwise movement of said shaft, :1 retarding spring opposing the rotation of said shaft, said springs forming means for returning said shaft to normal.

13. An automatic switch including a single endwise movable and rotatable switch shaft, a wiper carried by said switch shaft, a. bank of contacts, electromagnetic means for moving said shaft in a vertical direction against the action of a retarding spring, electromagnetic means for then rotating said shaft and wipers against action of a second retarding spring, said retarding springs being adapted to return said switch shaft to normal position when said wiper is rotated beyond said bank of contacts. 7

14. An automatic switch including a switch shaft provided with a contact maker, a bank of contacts, stepby-step electromagnetic means for moving said switch shaft downwardly and for then rotating the same to carry said contact maker into engagement with one of the contacts of said bank, sprin means opposing the movement of said she t in both of said directions, said spring means being adapted to return the switch shaft to normal position.

15. An automatic switch including a mounting frame, a pair of bifurcated lugs attached to said mounting frame, a pair of bank rods adapted to fit into the bifurcated portions of said lugs, and a pair of nuts for each of said rods for securing said rods in position and for permitting adjustment of the bank.

16. An tlUtOlYHl-tlfi switch including a movable switch shaft adapted to he moved in a lineal direction and to be rotated, a movable contact carried by said switch shaft, a mem bcr secured to said switch shaft carrying said contact. off-normal contacts, and means actuated by said member for controlling said ofi'-normal contacts.

17. An automatic vertically and rotatably movable switch including a switch shaft, a wiper carrying member secured to said switch shaft, off-normal springs, and means operated by said wiper carrying member for actuating said off-normal springs.

18. An automatic switch including a mounting frame, a vertically and rotatably movable hollow switch shaft supported by said frame, and a spring extending through the hollow of said switch shaft opposing the movement of said shaft.

19. An automatic switch including a hollow switch shaft, a bank of passive contacts. a. movable contact carried by said shaft for engagement with said passive contacts, and a spring extending through the entire length of the hollow in said switch shaft for opposing the movement thereof.

20. An automatic switch provided with a downwardly movable and rotatable switch shaft carrying switch wipers which partake of the same movement as the switch shaft, a spring opposing the endwise movement of said switch shaft. and a. second spring opposing the rotatable movement of said switch shaft.

21. An automatic switch including an endwise movable and rotatable hollow switch shaft, :1 spring extending through the hollow in said switch shaft opposing the endwise movement of the same, and a second spring encircling the said switch shaft opposing the rotary movement of said switch shaft. 7

22. An automatic switch provided with a switch shaft, a magnet provided with a pawl for moving said switch shaft, and a-member formed integrally with the heel iron of said driving magnet for limiting the return movement of said driving pawl.

23. An automatic switch including a switch shaft, a driving pawl for moving said switch shaft, and a retaining pawl and a guiding pawl for said driving pawl formed integrally with each other.

24. An automatic switch including a switch shaft, a rotary ratchet for rotating said switch shaft, a key-way cut in said shaft, a feather pivoted to said rota ry ratchet and adapted to engage the key-way in said shaft, and means for moving said 'l'cathcr out of engagement with said key-way when said shaft is being restored.

25. An automatic switch including a switch shaft, a rotary ratchet for rotating said shaft, a slot cut in said shaft, 21 hey pivoted to said rotary ratchet and adapted to lit into said slot, and means "for removing said key from said slot when the release of said shaft is desired.

26. An automatic switch including a movable switch shaft, a magnet for moving said switch shaft, an armature for said magnet, a driving pawl pivotally secured to the free end of said armature, and an angularly shaped spring secured to said armature having its free end lying flat against the ha k oi said driving pawl for pressing the same into engagement with the notches o i said switch shaft when said magnet is operated.

27. An automatic switch including a movable switch shaft, driving magnet For said switch, an armature provided with a pawl attached to its free end for said magnet l'or moving said switch shaft. and a heel iron for said magnet provided with integrally formed ends adapted to limit both movements of said driving pawl.

28. An automatic switch including a switch shaft, a driving magnet for said switch shaft, a driving pawl controlled by said driving magnet, and a pair of guides for guiding said driving pawl into and out of engagement with teeth on said shaft, said guides being formed integrally and pivotally attached to the extended end of the heel iron of said electromagnet.

29. An automatic switch including a. movable switch shaft. a driving magnet. an ormature provided with a driving pawl for said magnet for moving said switch shaft, and a pair of limiting stops for said driving pawl formed integrally with the heel iron of said clectromagnet.

30. An automatic switch including an endwise movable switch shaft. a rotary ratchet associated with said switch short for rotating the sa'mc, a rotary holding pawl. a member controlled by said switch shalt for actuating said holding pawl, rotary off-normalj springs, and a member secured to said rotary ratchet foroperating said rotary offnormal springs and for use in releasing the switch: shaft.

3.1. An automatic switch including an and wise movable and rotatable switch shaft, a rotary ratchet associated with said switch shaft, rotary off-normal springs, a holding member for preventing the return endwiso movement of said switch shaft, and an element secured to said rotary ratchet for operating said rotary off-normal springs and said holding member.

32. An automatic switch including a ver tical and rotary switch shaft, vertical oil normal springs, a rotary holding pawl. and a member controlled by said switch shaft for actuating said vertical off-normal springs and said rotary holding pawl.

33. An automatic switch switch shaft, a ratchet for rotating said switch shaft, :1 vertical slot cut in said switch shaft, a member pivotally secured to said ratchet and provided with an end portion adapted to fit into said slot, and means for moving said end portion out of engage ment with said slot when said soaft is being restored.

34. An automatic switch including an cudwise movable and rotatable switch shaft, bearings for said switch shaft, adjustable means for limiting the normal vertical position of said shaft, and a spring for returning said switch shaft to normal fastened to said adjin-table means.

35. An automatic switch including an endwise movable and rotatable switch shaft, bearings for said switch shaft, adjustable means for limiting the normal vertical position of said shalt, adjustable means for limiting the normal rotary position of said shaft, and a spring for returning said switch shaft to normal. fastened to said first adjustable means.

36. An automatic switch including a bank of contacts, a pair of plates between which. said contacts are secured, extended portions for one of said plates bent back parallel to the plane of the said plate, orifices for said plates through which bank rods extend, and screws having screw-threaded engagement with the bent back portions of said extended ends for securing the bank in place upon said bank rods.

3?. An automatic switch including a mounting plate, a pair of bank rods secured thereto, a bank of contacts mounted between a pair of plates, extended portions for one of said platebent hack parallel to the plane of said plate, orifices in said plates through which said bank rods extend, and screw members having screw-threaded engagement with the yoke portions of the extended bent back portions of said plate for sew curing said bank of contacts to said bank rods.

38. An automatic telephone exchange system including a subscriber-s telephone line, an automatic selector switch for extending a call from said. line an impulse relay for said swit h controlled over said line, a differential secondary relay controlled by sai il impulse relay for controlling a secondary including a switching circuit, a test. relay and a driving magnet for said switch, a circuit for said test relay including a contact of said driving magnet, and a circuit for said driving magnet including a contact of said test relay.

39. An automatic telephone exchange system including a suhscrihers telephone line, an automatic selector switch for extending a call from said line, an impulse relay for said switch controlled over said line, a test magnet and a driving magnet for said antomatio switch, circuits for said driving magnet and said test magnet controlled by contacts of each other, whereby when one. of said magnets is energized it operates to (lo-energize the other of said magnets. and a differential release relay responsive to a prolonged de-energization of said impulse relay for controlling release means of said automatic selector.

40. A telephone system including subscribers line circuit, a two-wire automatic switch, automatic means for connecting said subscribefis lino circuit to said autoniaiic switch, an impulse relay for said switch, a transmitter connected in said line circuit. for interrupting the circuit of said impulse relay, thereby causing said relay to be inter-- mittently operated. a dillcreutial relay controlled by Said impulse relay for controlling a switching circuit, a test magnet and a motor magnet for said switch. and circuits for said motor magnet and said test magnet controlled by contacts of each other, where by when one of said magnets ener it operates to Clo-energize the other of said magnets.

41. A telephone system including a. subscrihers line circuit, an automatic switch adapted to be connected to said line, an impulse relay for said switch, a differential relay for said switch operated to attract its armature responsive to the first operation of said impulse relay, :1 neutralizing winding for said differential relay effective upon a prolonged energization of said impulse relay to cause the retraction of its armature, a test magnet and a motor magnet. a cii ruit for said test magnet controlled l: 3. id differential relay, and circuits for said motor magnet and test magnet controlled by contacts of each other, whereby when our of said magnets is energized it operates to die energize the other of said magnets.

42. A telephone system including a subscribers telephone line, an automatic selector switch adapted to be connected to said line, a test relay and a driving magnet for said automatic switch, a circuit for said test relay including a contact of said driving magnet, a circuit for said driving magnet including a contact of said test relay, and means controlled by said driving magnet for restoring said automatic switch.

43. A telephone system including an automatic switch provided with wipers, a motor magnet for advancing said wipers, a test magnet, circuits for said motor magnet and said test magnet controlled by contacts of each other. whereby when one of said magnets is energized it operates to ole-energize the other of said magnets, and release means for said automatic switch controlled by said motor magnet.

4%. A telephone system including an automatic selector switch provided with movable contacts, a motor magnet for advancing said movable contacts, an auxiliary relay, a circuit for said motor magnet and said auxiliary relay controlled by contacts of each other, whereby when one of said magnets is energized it operates to tie-energize the other of said magnets, said motor magnet adapted to also control the release of said automatic switch.

45. A telephone system including an automatic switch having motion in two intersecting planes, a motor magnet and an auxiliary magnet for said switch, a circuit for said motor magnet including contacts of said auxiliary magnet, a circuit for said auxiliary magnet including contacts of said motor magnet, and a supplemental circuit for said motor magnet for controlling the restoration of said switch.

46. A telephone system comprising a telephone line, an automatic switch for extending a connection from said telephone line in the direction of a called subscribers line, an impulse relay for said switch responsive to circuit changes in said telephone line, a difl'erontial secondary relay responsive to said impulse relay for controlling a secondary circuit, a test magnet included in said secondary circuit, a motor magnet, a circuit for said motor magnet controlled by said test magnet, a circuit for said test magnet controlled b a contact of said motor magnet, and a di erential release relay responsive to a prolonged de-energization of said impulse relay for effecting the closure of a release circuit.

47. A telephone system comprising a subscribers telephone line, a two-dimension switch for extending a connection from said line having one motion for electing groups of trunk lines and a second motion for se lecting an idle trunk in an elected group of trunk lines, a diiterential secondary relay for controlling the second of said motions, a test magnet adapted to be controlled by said differential secondary relay, a. motor magnot adapted to be controlled by said test magnet and circuits for said two magnets including contacts of each other, and a differential release relay for controlling the release of said switch.

-18, A telephone system including an automatic selector switch, a relay and a motor magnet for said switch, a circuit for said relay controlled by a contact of said magnet, a circuit for said magnet controlled by said relay, and release means controlled by said magnet.

at). A telephone system including an automatic selector switch having motion in one direction to select groups of lines and in another to select lines in the groups, a relay and a motor magnet for said switch. a circuit for said relay controlled by a contact of said magnet, a circuit for said magnet controlled by said relay, and release means controlled by said magnet.

50. A telephone system including an automatic selector switch, a relay and a motor magnet for said switch, a circuit for said relay controlled by a contact of said magnet, a circuit for said magnet controlled by said relay, and a differential release relay for said switch.

51. A telephone system including an automatic selector switch, a relay and a motor magnet for said switch, a circuit for said relay controlled by a contact of said magnet, a circuit for said magnet controlled by said relay, and a differential switching relay for said switch.

(2., A telephone system includin an automatic selector switch, a relay and a motor magnet for said switch, a circuit for said relay controlled by a. contact of said magnet, a circuit for said magnet controlled by said relay, and differential switching and release relays for said switch.

Signed by me at Chicago, in the county of Cook and $tate of Illinois, this th day of June, 1917.

HARRY H. IDE. 

